Kim Duong was operating the shot blast machine at about 10 a.m. Monday, Aug. 25, when two fabricated metal guards that were placed around the front of the machine fatally struck him, according to a statement from the Michigan Department of Licensing and Regulatory Affairs.

Each of the metal guards weighed 632 pounds, the statement said.

"The guards were there because they were running a part in the shot blaster that was so large the doors could not be closed," the statement said. "The operator had climbed underneath the guards and bumped them causing the guards to fall onto the employee, crushing him."